1. Field of the Invention
The field of the invention relates to orthodontistry, and, more particularly, to an orthodontic prefabricated band gauge for determining the correct orthodontic band size for a tooth.
2. Description of the Related Art
The orthodontic treatment of the posterior part of the orthodontic cavity is similar to the treatment for molar and pre-molar teeth. The use of pre-fabricated orthodontic bands cannot be prescinded or put aside because these teeth are the basis of movement performed over other teeth. Because these teeth differ in measurement and shape, a measurer of pre-fabricated orthodontic bands must determine the exact measurement of the tooth in order to choose the exact band needed for the tooth in orthodontic treatment.
An orthodontic pre-fabricated band is a ring shaped band usually made of metal. The orthodontist places the orthodontic pre-fabricated band around the tooth and selects the bands to be used. The selected pre-fabricated orthodontic band is then cemented. The band is then crimped tightly about the tooth and the cement is let dry, completing the procedure.
It is critical that the size of the band chosen by the orthodontist is correct because the band is permanently cemented to the tooth. Moreover, orthodontic bands come in different shapes to accommodate different types of teeth, such as bicuspids, and molars. Since the teeth vary in size and shape, an orthodontist cannot rely on judgment alone, but must measure the circumference of the particular tooth fitted for an orthodontic band with an orthodontic instrument.
A circular micrometer is commonly used as an orthodontic instrument to measure the millimeter circumference of a tooth in order to aid an orthodontist in selecting the size of an orthodontic band. Generally, a circular micrometer is a device used to measure any cylindrical object, the micrometer having one end of a flexible tape measure fixed to an elongated bar and the other end slidably mounted along the bar such that a loop is formed at an end of the micrometer. The loop is placed around an object and the tape is slidably adjusted along the bar to tighten the loop about the object. The micrometer includes a scale so that an operator may read the circumference measurement of the object. In orthodontic practice, the circumference of a tooth is measured and an orthodontic pre-fabricated band size is selected to be fitted on the tooth.
Orthodontists have found that the circular micrometer is inadequate for prefabricated orthodontic band measurement because this device was not devised specifically for orthodontic practice. Different orthodontic bands must actually be placed on the tooth to determine the correct band size even when using a circular micrometer. More importantly, improper selection of the orthodontic band size has often caused patients to return to the orthodontist's office to have cemented orthodontic bands replaced. What is required is an orthodontic instrument that indicates the correct size of a prefabricated orthodontic band for a tooth more accurately, so that the number of orthodontic bands attempted for fitting on a tooth is reduced.
Oral infections, a patient's comfort and cost are three basic factors that need be considered when devising any new orthodontic instrument for more accurately measuring the correct orthodontic pre-fabricated band size of a tooth. Such an orthodontic instrument will satisfy these three factors by performing more efficiently.
First, orthodontic instruments should be designed to reduce the possibility of oral infection. The instrument should be easily sterilized, and also should increase the efficiency of orthodontic procedures so that less time is required working within a patient's mouth, therefore creating less of a chance for an oral infection to occur. An orthodontic instrument must especially aid in preventing oral infections because this device is in direct contact with the traumatized orthodontic tissue. Repeated placement of orthodontic bands during a fitting on a patient's tooth will cause the gums to be irritated, further increasing the risk of infection. In the case where a cemented orthodontic band needs to be replaced, greater trauma is caused to the orthodontic tissue and the risk of infection is again increased.
Second, an orthodontic instrument for more accurately determining an orthodontic band size should be designed to be comfortable to a patient.
Third, an orthodontic instrument for more accurately determining an orthodontic band size should reduce the cost of the orthodontic procedure. Each orthodontic band that is fitted on a tooth and is found to be the incorrect size must be thrown away at cost for purposes of sanitation.
In summary, an orthodontic band gauge with an indicator is needed to indicate the correct size of prefabricated orthodontic bands for a particular tooth thereby decreasing the likelihood of oral infection, discomfort to the patient and cost. Specifically, such a gauge should lock the indicator in place so that a correct reading of the orthodontic band size is achieved despite removing the gauge or shifting of the patient. Further, the gauge must allow an operator to tighten the gauge loop firmly about the tooth to achieve a correct reading because the loop material may be substantially rigid to fit between tightly spaced teeth. In addition, the indicator should be easily read.
The prior art does not fulfill the need for an orthodontic band gauge that determines the correct prefabricated orthodontic band size because the prior art offers a mere circular micrometer. For example, U.S. Pat. No. 2,231,121 issued to Hormann discloses a band-type micrometer that does not consider the above objectives. This device consists of the common features of a circular micrometer, having a loop for measuring the circumference of teeth and a slidable member that adjusts the size of the loop. As discussed, a circular micrometer similar to the disclosed Hormann device is inadequate as an orthodontic instrument for more accurately determining an orthodontic band size. Hormann nowhere teaches the use of this micrometer for determining correct orthodontic band sizes. Further, this device utilizes mere friction forces to lock the slidable member in place. As discussed, an orthodontic band gauge must be able to indicate the correct orthodontic band size even when fitted between tightly spaced teeth, removed from the teeth or jostled by the patient. The arrangement disclosed by Hormann is inadequate to indicate an orthodontic band size accurately under these conditions because the friction force is not sufficient to lock the slidable member in place for a correct measurement.
Further, Hormann does not disclose any device that pulls the loop sufficiently tight about the tooth. The slidable member is operated manually and is inadequate to tighten the device, especially when an orthodontist must operate from within the patient's mouth. A particular problem with the Hormann device is that it discloses a loop that has one end attached to the device. If the loop is pinched between teeth, the loop will be unable to tighten past the pinching point because the loop only tightens from one side.
In addition, Hormann does not disclose any means by which the device is easily read. An orthodontist must read the measurement while the Hormann device is within the mouth, attached to a tooth. This increases the likelihood of an incorrect orthodontic band fitting because the device is difficult to read inside a mouth or might be thrown off due to the orthodontist's relocating the device in order to read the measurement.
In conclusion, the Hormann device does not fulfill the requirements of an orthodontic band gauge and, therefore, would not adequately measure the correct band size for a particular tooth. As a result, this device would not be adequately sanitary, painless and inexpensive.